My Only Weakness Is Knowing Your Secrets
by moonlightBuffy
Summary: AU. Faced with death, a mysterious figures offers Arthur a time to go back to his youth to change everyone's future. Morgana/Arthur
1. Prolouge

******Notes:** I got inspired by some summary I saw here on and I thought I'd make a Merlin timetravel fic myself. I'll update this as much as I can but I've already written a lot so I think I'll definitely finish it. Please leave feedback if you want, I'd really appreciate it. Helps me grow as a writer. This fic is mostly gen but with Morgana/Arthur undertones (we'll see how it develops).

**Prologue**

He was tired and weary. Death was made for old men with tired hearts. As he was lying on the battlefield, knowing that this was the end, he couldn't be angry. Not with the man who was standing over him, holding his own sword to kill him with it. The sign of his worthiness. The promised king. It had been his destiny to make Camelot better. Instead he had failed.

Just as the metal was about to pierce his flesh, he saw a figure emerge from the mists, cloaked in mystery. Mordred could not yet see her, but Arthur could see her approaching as he awaited his death. Somehow Mordred's deathly blow seemed to linger and it did not take long for Arthur to realise that he was frozen. Even though the shape that approached him did not seem to want him harm, Arthur felt a terror unlike anything else had ever felt in his entire life. Magic had always scared him. Perhaps it was a legacy of his father but ever since he had learned of the circumstances of his own birth, he could not help but feel helpless in its presence.

"Arthur Pendragon," the voice said - not speaking but speaking in his mind. The voice was cold and hollow but somehow soothing. "Do not fear me. I am Viviane and I am here to help."

Even though his lips weren't moving, he could hear his own questions in his mind being asked to this ghostly phantom that had so mysteriously appeared in the midst of blood and war. "Why do you want to help me? After everything I have done to your people?

"The balance is wrong. Things were not supposed to happen this way. You have a choice to stop everything that you have yet lived from coming to pass. But this is not an easy task. You have to be prepared for the responsibility this means."

"How? How will I do that?" If he truly had the chance to change everything from coming to pass it wasn't much of a choice. There wasn't a choice. What he had to do was clear as day. Things could not end this way.

"You'll have to go back in time, Arthur Pendragon. There isn't a lot of magic in me left but I have enough to send you back. All I ask in return is that you give me your word that you will stop Uther from prosecuting my kind and that you save Morgana."

The last promise had an eery feel to it. "Why Morgana? What do you want with her?"

"Just as you are promised to the people of Camelot to be their next great king, Morgana is promised to us. To save us. It is important you do not let her fall into this darkness. Do you understand?"

He looked at her terrifying form, for a moment at a loss for words. Slowly, however, his head began to nod and he could immediately feel the weight of this promise on his shoulders. There was perhaps a time in his life where he would have taken promises lightly but it was not today, not this close to death. His honour was the only thing he had left.

What happened next was difficult to describe, but it felt as though he was lowered into a cold pool of water without getting wet and before he knew it, a warm sensation spread through his body before everything turned black.

He was going back. To save everyone.


	2. The Gifted Curse

Chapter One: The Gifted Curse

When Arthur finally woke up, the first thing he heard was the sound of birds chirping from outside his window. There hadn't been birds in Camelot for years. The war had scared them all away. All except the crows. For a moment, it was as though he was in a haze, as though all of his memories of the war was just a dream but as he woke up, reality came back and he remembered the mysterious woman, whom had just saved him from a certain death. The whole experience was so bizarre and confusing that for a moment, he entertained the notion that perhaps it wasn't a memory at all but a fever that he had struck him and that while he thought he was back at Camelot before the war, he was actually in his sickbed in the midst of war.

Perhaps Mordred hadn't killed him at all.

But as he opened his eyes and saw his old room, he knew that it was no dream. The scent of wood lingered in the air and the air was fresh and crisp. Not stained with blood and heavy with people's cries of pain. There was definitely not a war here. He hadn't slept in this bed for years and everything was just as it once had been. There was no logic to his current state but then again, magic had always been incomprehensible to him. Some said that you could feel it in the air, but for Arthur it just appeared. He could never feel it. Perhaps it was just an old wife's tale made to scare children.

His solace was interrupted by the entrance of a familiar, much younger face. Merlin was suddenly standing his doorway, holding his shirts like he had once done. Arthur had to keep himself from expressing the full extent of his joy to see his old friend. The war had kept them parted for so long that he barely remembered what Merlin looked like. But then again, back there they were both old men now. Neither of them looked like they used to.

"Arthur, are you up yet?" Merlin's eyes narrowed slightly in disapproval and Arthur remembered that this was once how they used to be - simple and easy. Before, all of their conversations had ended in disagreements, yelling and talk of deaths. It was a pleasant change. "I see you're not." He added to emphasise his disapproval and Arthur couldn't help but grin. That made Merlin cautious. "What's wrong with you?"

Oh. Right. Back then he had been an entitled prince, too afraid to admit even to his friends that he cared about them. He wasn't sure exactly what year it was but he had been young for a long time and the war had forced him to grow up fast.

"Ehm, nothing. I was just wondering what that on your face was but then I realised that was just... your face." Sarcasm was a skill he had to forsake.

"Right." Merlin didn't look convinced. "Well, you should've been up an hour ago because that envoy the king wanted you to meet is coming very soon. I'll come back in a few minutes and then you better be up."

Arthur rolled his eyes. "Yes, mother." He had forgotten how fastidious Merlin had been.

He thought he saw Merlin grin as he closed the door behind him.

Even though he was there on serious business and with a tough task with no idea where to begin, Arthur was glad to be back. Who had not wanted to go back in time to change their mistakes? And back here, he had done so many that he was glad for the opportunity to change them, even if it would be difficult as he would have no idea what would be beyond the next step. Besides, being back here was a bit like reclaiming his youth too. He had been so blind and self-obsessed that he was happy to make sure that he made things right this time. Starting with growing up quicker, because he had spent too long in the shadow of his father and that had not learned him to make decisions quick enough.

Most of what had happened in Camelot had been due to his own ignorance and his youthful mistakes. He wasn't about to do the same thing twice.

Realising that the first step in that direction was to get up, Arthur shot out of bed like an arrow and dressed quickly, just as Merlin was entering the room again. Merlin stared at the sight in amazement.

"I was just going to help you with that, sire."

Arthur shook his head. "No, it's okay. I can dress myself." Years of war had made him have his priorities. "This way you can spend the morning doing your other shores, like my armour and so on, instead of waiting on me."

Merlin stared at him with such amazement that Arthur couldn't help but feel a little bit annoyed. Surely he hadn't been that bad? "What?"

"I didn't even think you knew what it was I did for you," Merlin stated simply. "I mean, just the other day you said I could go and spy on that noble lord's daughter to see if she was pretty because, I quote, 'What else do you have to do?'."

Arthur didn't know if he should laugh or be ashamed. "Well," he began, "I do know. Now please stop asking so many questions. Where's this envoy arriving now again?"

Even though he had asked Merlin to stop asking so many questions, he could still feel his man servant's eye on him as though he was checking to see if he was possessed. "In the Great Hall, sire. Your father thought it best to meet under as formal circumstances as possible. Apparently it's some sort of priestess from the Fairy Islands."

Arthur nodded. His father had always despised priestesses of the old religion. Perhaps it was because during their visits, Uther had to make sure that he kept his prosecution of those with magic under wraps, as to not invoke their fury. Mostly this had been a useless task as his treatment of gifted people was already common knowledge among everyone, especially those with magic. But then again, he hadn't known that at the time.

Walking through the halls of Camelot was strange. It wasn't filled with refugees, coughing children and broken walls. Instead it was nice, neat and rather empty as it was still peacetime. As he walked down to the Great Hall, he saw several guards and it made him feel uneasy, as he could remember when each of them would die.

But I have a chance to stop it, he reminded himself. Perhaps I can stop anyone from dying?

Just as he was about to walk in, a familiar voice caught him off guard. "Arthur!"

Arthur spun around and came face to face with his sister. It was so strange seeing her like this - still dressed as a princess, her beauty carefully maintained and a seemingly easy walk. This had been a time when the only thing that had haunted her was uneasy sleeps and not the death of her people, the revelation of their relation and her murder of their father. Even though he wasn't her favourite person at this time, she still managed to smile when she saw him, even if it was just to mock him.

"I see you just got up. I'm sure Uther will be so proud. Perhaps the most important meeting of the month to keep the Fairy Islands in place and you look as though you've been through a war." Her voice was sarcastic and filled with dry humour, but Arthur's mind flashed with images of real wars and he couldn't laugh.

Even in spite of everything Morgana had done in... well, his past and her future, he couldn't hate her. Everything had been so wrong then and he knew her well enough to know that she could never be a bad person. It had just been a bad situation. He was back now to change all that and he imagined that the most important thing about it all was to make sure that she did not kill their father. It had been after that when her fate had been truly sealed. Any time before then, he could still save her. Make sure that she was happy.

Because that was what siblings did.

And he was going to treat her better. He was.

Morgana paused with her amusement, carefully analysing his face. "Is everything okay, Arthur? You seem... a little bit off."

Arthur shrugged. "I'm just a bit tired."

The time travel was already beginning to mess with his head. Standing there, talking to his self-professed enemy on friendly terms felt so bizarre, as though he had entered into an alternative universe. A world where everything had been easy.

"Couldn't sleep?" Suddenly Morgana's face was pained with sympathy and Arthur saw the deep, dark circles under her eyes, remembering just how much her nightmares used to torture her. Of course, back then he had thought she was just being overdramatic and never paid much attention to it. There had been so much about her that he had simply ignored because he had been too busy trying to win his father's approval.

"I'll be fine," Arthur promised and lightly squeezed her hand before entering the Hall. Morgana followed soon after.

Uther was already in place at his throne and upon seeing his children, his nerves were obviously softened. "You're late," he remarked with a hint of disapproval that Arthur was surprised to learn no longer stung. He was already grown up and been through all of this before. Considering the choices Uther had made, he had no need to justifying himself to his father. He was going to be a better king than him and for that to happen, he needed to take his future task seriously.

"I overslept," Arthur said and sat down at the place of the intended heir. Morgana placed herself naturally on the other side of their father and Arthur couldn't help but glance over at her. Did she know already that Uther was her father too? Did she want the throne? It seemed from what he was seeing that it was not the case. Morgana was simply sitting there, staring straight ahead, waiting for their guest to arrive.

"The envoy from the Fairy Islands will be here at any moment," Uther snapped, "We cannot afford to make anything go wrong."

"Where are the Fairy Islands, anyway?" Morgana asked, looking at her father suspiciously. Even if she had no idea about the depth of Uther's betrayal, she still wasn't okay with his political decisions.

"It's a group of islands about three days boat ride from here. They are technically under Camelot rule but have been practically independent for a couple of years," Arthur answered before he could stop himself. Both his father and Morgana stared at him in amazement. "What? I read." He added quickly, realising that it was perhaps best if he didn't start raising too many questions.

"I just didn't think politics interested you," Uther remarked dryly, "Especially since those islands are full of magicians whom have been wanting me off the throne for years. This is a delicate matter."

Only because you have been killing their people for years and hope to get away with it. Even though his own rule had been plagued with problems, his own experience had learned him not to take everything Uther said so lightly. War had a tendency to reveal everyone's good and bad sides.

Suddenly, a guard appeared. "Lady Viviane, High Priestess of the Island of Avalon."

Arthur's attention was suddenly captured as the envoy approached. She was tall and magestic, her face glowing of knowledge and power, and Arthur remembered her face as clear as day. It was the cloaked figure from the battlefield. Even though it was years and years into the future, she looked exactly the same. The priestesses of the islands had always been blessed with long lives.

She had a curious talent to make it seem as though her eyes were on him, even though her eyes were fixed on Uther. It wasn't until she approached the throne that her eyes came on him and Morgana. Arthur paid close detail to the way Viviane surveyed his sister and he could see that her eyes glimmered with approval. Even then she had known, known of the trouble that haunted his sister. Morgana had even noticed Viviane's special presence and was looking at her with an awareness unlike anything he had ever seen before. Perhaps magic could be felt after all?

"My king," she said honourably as she kneeled but to his surprise, her eyes turned to Arthur as she said those words. The determined stare of her gaze made him feel uneasy. As though she knew. As though she could stare into his soul and know where he was from. He could see Morgana turn to stare at him in surprise but the gesture had completely escaped Uther's attention. Which was probably just as well.

"Viviane," Uther greeted her and rose from his throne to embrace her as he would an old friend. Politics for Uther had always been a little bit of a game. It was as though he was acting, telling everyone that he was their best friend, although Viviane could see through his game right away. Seeing his father now, Arthur could not admire him as he had once. Instead, all he could see were mistakes and wrongs that needed to be made right. That was perhaps the most painful thing about being back. Even though it was peaceful now, there was no peace for him to be had. Even though he was back in the past, he was still on a battlefield, only he was fighting their future - everyone's future - from coming to pass.

"How was your journey? Was it tiresome?" Uther enquired courteously, "I shall make my servants take you to your chambers immediately before our talks commence, if you wish."

Viviane shook her head. "That is quite all right, Uther. The journey did not wear me out. What would make me happy though, would be to see your lovely children," It was both infuriating and funny how Uther immediately tensed up, "Your son and your lovely ward. You have both grown up so much since I saw you last." Viviane turned to them now, glancing at them both in turn.

"Have we met before?" Morgana asked curiously.

"It was a long time ago now, I doubt you'll remember. You were only three at the time," Viviane smiled.

The memories of times past made Morgana smile and immediately Arthur could tell that she was warming to their guest, which undoubtedly made Uther nervous. Seeing as though it was time for him to make his presence known, Arthur stood up from his princely stool and approached Viviane to shake her hand.

"I'm Arthur. It's nice to meet you again, Viviane, even though I don't recall your face." A straight up lie, of course. He knew he would remember her face until the day he died.

Viviane took his hand, her hands being placed over them in accordance with Avalonian tradition. They were warm and soft, not at all the hands he imagined a priestess to possess. "You have grown up so much, I see. Perhaps I am getting nostalgic but it feels as though I only saw you yesterday."

The knowing smirk that followed caught Arthur off guard. Did she know? There was definitely some indicators in her face but he could not be sure. Perhaps it was because of his own fantastic birth or his recent exposure to magic, but Viviane could definitely sense something about it.

"How long has it been since your last visit to Camelot?" Arthur asked, ignoring the nervous stares of his father behind him.

"Oh, too many years to count. We generally keep to ourselves in the Fairy Islands, although the occasional news do cross our paths."

Arthur grinned. Viviane was intelligent. Even though the remark was pleasant and common enough, he could sense the threat lying underneath it and therefore the futile nature of Uther's attempts to keep his persecutions a secret. Viviane and the rest of the Islands already knew, they had only sent her as an attempt to mend the bridge. To give Uther a final warning before their revenge would commence.

"Then you must allow me to show you around, Camelot, priestess. It would be an honour."

"That would please me indeed, prince Arthur. I'm sure we'll have lots to talk about."

"I'm sure we do."

There was no doubt in his mind now. Viviane knew. She knew everything.


End file.
